Document 0173 DOCN M9620173 TI Mutation of Jak3 in a patient with SCID: essential role of Jak3 in lymphoid development. DT 9602 AU Russell SM; Tayebi N; Nakajima H; Riedy MC; Roberts JL; Aman MJ; Migone TS; Noguchi M; Markert ML; Buckley RH; et al; Laboratory of Molecular Immunology, National Heart, Lung, and; Blood Institute (NHLBI), National Institutes of Health (NIH),; Bethesda, MD 20892, USA. SO Science. 1995 Nov 3;270(5237):797-800. Unique Identifier : AIDSLINE MED/96055115 AB Males with X-linked severe combined immunodeficiency (XSCID) have defects in the common cytokine receptor gamma chain (gamma c) gene that encodes a shared, essential component of the receptors of interleukin-2 (IL-2), IL-4, IL-7, IL-9, and IL-15. The Janus family tyrosine kinase Jak3 is the only signaling molecule known to be associated with gamma c, so it was hypothesized that defects in Jak3 might cause an XSCID-like phenotype. A girl with immunological features indistinguishable from those of XSCID was therefore selected for analysis. An Epstein-Barr virus (EBV)-transformed cell line derived from her lymphocytes had normal gamma c expression but lacked Jak3 protein and had greatly diminished Jak3 messenger RNA. Sequencing revealed a different mutation on each allele: a single nucleotide insertion resulting in a frame shift and premature termination in the Jak3 JH4 domain and a nonsense mutation in the Jak3 JH2 domain. The lack of Jak3 expression correlated with impaired B cell signaling, as demonstrated by the inability of IL-4 to activate Stat6 in the EBV-transformed cell line from the patient. These observations indicate that the functions of gamma c are dependent on Jak3 and that Jak3 is essential for lymphoid development and signaling. DE Amino Acid Sequence Animal B-Lymphocytes/*IMMUNOLOGY Base Sequence Case Report Cell Line, Transformed Female Frameshift Mutation Human Infant Interleukin-4/PHARMACOLOGY Linkage (Genetics) Molecular Sequence Data Phenotype Point Mutation Protein-Tyrosine Kinase/DEFICIENCY/GENETICS/*PHYSIOLOGY Receptors, Interleukin/PHYSIOLOGY RNA, Messenger/GENETICS/METABOLISM Severe Combined Immunodeficiency/*ENZYMOLOGY/GENETICS/IMMUNOLOGY Signal Transduction Support, U.S. Gov't, P.H.S. T-Lymphocytes/*IMMUNOLOGY Trans-Activators/METABOLISM X Chromosome JOURNAL ARTICLE SOURCE: National Library of Medicine. NOTICE: This material may be protected by Copyright Law (Title 17, U.S.Code).